In north Bavaria, right next to the A93 motorway, one of the largest industrial park expansions in Germany is currently under construction. The contract for the earthworks for the automotive supplier and technology park in Hof-Gattendorf was awarded to ARGE AMAND Bau Sachsen GmbH & Co. KG together with AMAND Bau NRW GmbH & Co. KG. From the end of July to mid-November 2020, approx. 150,000 m³ of topsoil and around 680,000 m³ of soil is being moved, paved and stabilised over a total area of 50 hectares. Only the best subgrade achieves optimum load bearing capacity for infrastructure and buildings. Consequently, soil stabilizers are being deployed to improve a large part of the 680,000 m³ with binding agents.
"We have been a customer of BOMAG for more than 25 years and looked after by the Chemnitz branch throughout this period. That builds trust."
AMAND Bau is relying on the experience, the team and the vehicle fleet of MEIER Bodenstabilisierung GmbH. The company, which was founded in 1995 and is based in Oelsnitz/Erzgebirge, Saxony, specialises in soil improvement and stabilisation. With a fully equipped pool of machines, its own repair and maintenance facilities and a permanent workforce, the company covers the entire range of soil stabilisation. The family-run firm has aligned its entire business model to current and future requirements in this sector and is active throughout Germany and in neighbouring countries.
To achieve the required daily performance targets at the Hof-Gattendorf project, up to 580 t of binding agents need to be spread daily and milled into 13,000 m³ of soil. MEIER Bodenstabilisierung opted for three large BOMAG planers from their own fleet in order to meet the deadlines and required quality.
For this reason, three machine generations were used simultaneously in the project on the A93 motorway: an MPH 125, an MPH 600 and an RS 650. At first glance, it is hard to tell the stabilizers apart, as the manufacturer has adhered to the overall concept across all generations, while at the same time decisively improving details in terms of ease of use, performance and functions.
One thing all the machines have in common is, for example, the permanent 4x4 drive for best traction on very soft ground, as is the case with the Hof-Gattendorf project. When the specified daily output is as demanding as here, it is important to work fast. In addition to time pressure, the weather is an unpredictable factor, as is now the case in autumn. The more it rains, the more slippery and soft the ground becomes, which increases the demands on the stabilizers. The combinable articulated and rear-wheel steering on each machine generation ensures flexibility and maximum manoeuvrability for any ground condition. The height-adjustable cab has also been retained, ensuring the driver’s comfort and clear overview. The swivel and sliding seat provides the operator with an individual sitting position and thus optimum all-round visibility. Visibility is improved even further by four fixed cameras.
The visual differences between the MPH 125, MPH 600 and RS 650 first become apparent in the exhaust systems. Due to the new engines, the RS 650 with its 8-cylinder Deutz engine has a power output of 650 hp, while the two predecessors each mix the soil with 600 hp. The continuous improvements in engine technology also led to the introduction of stricter exhaust emission standards, which include significantly reduced limits for nitric oxides and particles. The latest generation of engines meets these environmental requirements. With the aid of a double SCR exhaust system, nitric oxides are converted into nitrogen and water by adding urea solution (AdBlue) and thus rendered harmless. The MPH 125, for example, has exhaust classification 3, the MPH 600 already has stage 3 B, and the RS 650 achieves stage 4.
Another difference is “hidden” beneath the milling hoods. All three machines are equipped with BOMAG’s FLEXMIX system. This makes it possible to optimally adjust the milling performance and mixing level of the different soils on site. Thanks to continuous improvements in the quick-change tool holders and their arrangement on the rotors, the working speed and service life have also further increased. And all this with an even better mixing result.
When compared directly on the A93 motorway project, these product developments are, of course, noticeable for the drivers. It is often just small details that simplify everyday work and make one or the other operation unnecessary. Hydraulic reversible fans, for example, keep the radiators clean for longer. When it's cold and wet outside, no one wants to spend a long time changing cutters anymore. Compressed air connections for tools and hydraulic turning devices for the rotor save time and greatly facilitate the daily inspection and replacement of cutting tools. The latest machine generation also provides the best possible lighting conditions thanks to 8 LED headlights. This guarantees safety—even on long working days.